Re: object removal from list causing core dump

[Doug Donalson;]

Here is some code that I think will let you use your while loop.
Once you get the id of the list member you want to remove, try this:

  index1= [list createIndex: [self getZone] fromMember: memberId];
  [index1 remove]; // This removes the member
  [index1 drop];

You should be able to use this inside the loop.  I think?  :-)
Let me know if this works.  Also, remember to drop both indexes
and if the object removed is no longer being used, drop it too.

Cheers,

   Doug


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On Thu, 21 May 1998, Geoffrey Schultz wrote:

> Hi,
> 
> I'm having a bit of problem with my simulation and was wondering
> whether I'm committing a no-no.
> 
> I have a list that will contain a variable but small number of
> objects.  If I set up the following code bit, I get a seg fault and core
> dump.  Is their something wrong with this:
> 
> index=[MyList begin: scratchZone];
> while((anObject=[index next])){
> 
> // check certain properties of the object and
> // if meets criteria:
> 
>   if(condition)
>       [MyList remove: anObject];
> 
> }
> 
> does removing a member while in a "while" statement cause a problem with
> indexing? The list initailly has only the single member (that is removed)
> but at other times in the simulation may contain more than one member.
> 
> I can supply the complete backtrace, however the last line 
> 
> says
> 
> -[ListIndex() at List_GEN.m: 295
> 
> (using ddd as debugger)
> 
> 
> Thanks,
> 
> Geoff Schultz
> 
> 
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